Protect against reading past the end of file and accessing an uninitialized value when reading a dump file.  This bug is mostly harmless, but it's better to be correct.
Use is_constant_struct instead of include_summand to resolve issue #389.  Still need to check other distributions to see if this is happening there.
Initialize pointers in OperandsAndPartials to NULL when the corresponding parameter is constant to crash on bugs in PDFs.
Remove redundant include_summand checks for code clarity.
Fix the binomial distributions use of OperandsAndPartials.
adding size() function to DoubleVectorView
updating error message from DoubleVectorView
removing setting of derivatives from cdf code.
changing implementation of OperandsAndPartials to return runtime errors instead of seg-faults when accessing invalid partial derivatives
removing setting of derivatives from cdf code.
changing implementation of OperandsAndPartials to return runtime errors instead of seg-faults when accessing invalid partial derivatives
Merge branch 'feature/issue-389' of https://github.com/stan-dev/stan into feature/issue-389
Revert "changing implementation of OperandsAndPartials to return runtime errors instead of seg-faults when accessing invalid partial derivatives"

This reverts commit 38190ec30fbc2c7f19d3745f3bee9d3c8adc4ab2.
Revert "updating error message from DoubleVectorView"

This reverts commit b5859d19f5d7ab5c20948461873d28633ba7947d.
Revert "adding size() function to DoubleVectorView"

This reverts commit 7869e7cd980bb84ec6c0a92179d3a5f26e950f6d.
updating VectorView to take an additional template parameter to throw when accessed; added tests
Merge pull request #423 from stan-dev/feature/issue-389

Fixes #389.